#define  _CRT_SECURE_NO_WARNINGS

int missingNumber(int* nums, int numsSize) {
    int n = 0;
    for (int i = 0;i <= numsSize;i++)
    {
        n = n ^ i;
    }
    for (int i = 0;i < numsSize;i++)
    {
        n = n ^ nums[i];
    }
    return n;
}
